Butchart, who will compete in the 5,000metres, claimed in a now-deleted episode of The Sunday Plodcast that he changed the test on a result to allow him to return to the UK after a race abroad.
"I'm not going to get in trouble from the police or anything like that," said Butchart.
"You have to get a Covid test to get into the UK, so you went to a place to get a PCR test before 48 hours – and I'm with check-in and I don't have my PCR test back.
"So you have to quickly, like, get an old PCR test, go on to Instagram, scribble out the time and the date, change the time and the date, and change it so you can get into the country.
"Obviously Covid is huge but it's quite annoying. Everybody has faked PCR tests, I’m sure, to try and go somewhere, because it’s just so hard."
Butchart told The Times that he had "perhaps glorified the situation for the podcast" and has since apologised to Team GB and Olympics organisers.
A statement from UK Athletics said: "Following widely publicised comments by Andrew Butchart on a podcast regarding the alleged faking of COVID tests, he was charged with misconduct by UK Athletics for making statements likely to bring athletics into disrepute.
Butchart has been given a 12-month ban, suspended for two years, and a £5,000 fine.
Additional reporting by Reuters.
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